One less lonely girl! Justin Bieber pulls his mother Pattie Mallette on stage for a Mother's Day tribute... as Selena Gomez calls their relationship 'absolutely over'

His romantic life is the fodder for millions of fans around the world.

But it wasn't his on-and-off again relationship with Selena Gomez that captured the hearts of Justin Bieber fans on Sunday -- instead it was his Mother's Day tribute at his sold out show in Johannesburg, South Africa.

Lonely no more: Justin Bieber planted a kiss on his mother Pattie Mallette as he serenaded her on stage for a Mother's Day tribute on Sunday

The 19-year-old surprised his mother Pattie Mallette with an on-stage serenade to his tune One Less Lonely Girl.

'Happy Mother's Day @pattiemallette. Today u r my #OLLG. Love u,' he tweeted after the show, referencing the title of his popular song -- which he usually performs with a lucky fan from the audience.

He also shared a snap of the precious moment in which he handed his single mother a bouquet of roses and clutched her tightly.

Fan favourite: The tune usually features a lucky fan pulled from the audience

'So yep.. @justinbieber surprised me for mother's day tonight & brought me out for OLLG! #verysweet,' the single mother wrote on her Twitter account.

And while he was busy serenading his mother, his are-they-aren't-they lover Selena Gomez finally put the nail in the coffin on their relationship.

The former Disney star confirmed she was 'absolutely available in every way' in an interview with Boston Kiss 108 on Friday.

Eat your heart out, Justin: Selena Gomez firmly stated that the pair are split during a radio interview on Friday

The radio host eased into the subject by asking the Spring Breakers starlet what she would say to a boy on the street who asked her out for ice-cream.

'You're available?' the Beantown DJ probed.

'Yep,' the former Disney star responded. 'By the way, that would be awesome if someone asked if I wanted ice-cream because that would be cool.'

Her own tribute: Selena Tweeted this picture on Sunday of her cradling her mother's baby bump

Selena, who turns 21 in July, recently described her on/off relationship with the Canadian crooner as 'crazy and intense.'

After splitting with Justin in December, the pair appeared to be rekindling the romance when the 19-year-old singer tweeted a snap of her cuddling his bare torso from behind.